title: Outcome measures in rheumatoid arthritis randomised trials over the last 50 years.
abstract: BACKGROUND
  The development and application of standardised sets of outcomes to be measured and reported in clinical trials have the potential to increase the efficiency and value of research. One of the most notable of the current outcome sets began nearly 20 years ago: the World Health Organization and International League of Associations for Rheumatology core set of outcomes for rheumatoid arthritis clinical trials, originating from the OMERACT (Outcome Measures in Rheumatology) Initiative. This study assesses the use of this core outcome set by randomised trials in rheumatology.
  
  
  METHODS
  An observational review was carried out of 350 randomised trials for the treatment of rheumatoid arthritis identified through The Cochrane Library (up to and including September 2012 issue). Reports of these trials were evaluated to determine whether or not there were trends in the proportion of trials reporting on the full set of core outcomes over time. Researchers who conducted trials after the publication of the core set were contacted to assess their awareness of it and to collect reasons for non-inclusion of the full core set of outcomes in the study.
  
  
  RESULTS
  Since the introduction of the core set of outcomes for rheumatoid arthritis, the consistency of measurement of the core set of outcomes has improved, although variation in the choice of measurement instrument remains. The majority of trialists who responded said that they would consider using the core outcome set in the design of a new trial.
  
  
  CONCLUSIONS
  This observational review suggests that a higher percentage of trialists conducting trials in rheumatoid arthritis are now measuring the rheumatoid arthritis core outcome set. Core outcome sets have the potential to improve the evidence base for health care, but consideration must be given to the methods for disseminating their availability amongst the relevant communities.
authors.affiliation: Department of Biostatistics, University of Liverpool, L69 3GA, Liverpool, United Kingdom. prw@liv.ac.uk.
authors.forename: Jamie J
authors.initials: JJ
authors.lastname: Kirkham
authors.forename: Maarten
authors.initials: M
authors.lastname: Boers
authors.forename: Peter
authors.initials: P
authors.lastname: Tugwell
authors.forename: Mike
authors.initials: M
authors.lastname: Clarke
authors.forename: Paula R
authors.initials: PR
authors.lastname: Williamson
mesh_terms: D001172:Arthritis, Rheumatoid / Q000175:diagnosis / Q000628:therapy*; D023381:Endpoint Determination; D019317:Evidence-Based Medicine; D006801:Humans; D017063:Outcome Assessment, Health Care; D011237:Predictive Value of Tests; D016032:Randomized Controlled Trials as Topic / Q000379:methods*; D012107:Research Design; D013997:Time Factors; D016896:Treatment Outcome